Hello,
I just installed a new intake manifold gasket, water pump, radiator, t-stat, radiator cap. Okay, I bled the radiator by raising the passenger side cap off, up to temp, let cool , repeat as needed. Still never went to 195*, okay air is the problem, so I kept the raised, brought the Rpm's up to 2000 with something holding it there,I stayed by the radiator watching little air bubbles come out of the top fin in the radiator, for over 1/2 hr, adding some coolant as needed, heat was on blowing nice and hot,temp gauge went to 195* ish kept it going till I didn't see no more bubbles, and seemed to be circulating pretty good in the radiator. I capped it, lowered the truck. that's it.
About 3hrs later my wife went out for about 30 min, she said temp gauge was at about 200*, heat was working , but then started to blow cooler air ! PLEASE advise, what could be going on here, I spent about 3 hours doing this yesterday. HELP !!!!!!

 

More air?

Do you still have the cooling system pressure tester? If you do, I would see if it holds 16psi. Pulling a vacuum on the system can help get air out.

Also, did you verify that your overflow tank was full and that the line from the tank to the radiator was free flowing?

 

It's full, And it's full flowing for sure, but I returned the tester. Can it be more air had risen to the top? I hope it isn't the head gasket ! But I really doubt it do you ? I can't fiquire it out though, when I had brought this up to 2000 rpm's I was getting small air pockets on the top fin of the radiator for at least 1/2 hr, till it stopped. Think there maybe just a little more air ? Remember when I pressure tested it only dropped ever so slightly then I seen the leaky intake. Maybe the air pocket is in the heater corenow? Is the core lower than the hoses through the firewall ?

 

how do the heater core hoses thru the firewall feel? Is one cooler than the other indicating a restriction of sorts-after all the work who knows why but.....If you had a digital thermometer you could read it exactly(and you may have)-this would ease any doubts. JP[&:]

 

I gotta check again but yesterday when I did the bleeding I did yesterday, they were burning hot ! Unless some crap came through the block and got in there, coolant is spotless .

 

Okay, I just checked the feed hose to the heater core, very hot, then the return seemed quite a bit cooler, So I removed the feed hose and laid an a piece of 1" hose over it. Then I got the peak backflush kit ($4.00) cut in a t on the return side (smaller hose) got a vise grip needle nose style, and cut off (crimped) the towards the engine. Hooked a garden hose up to the T and turned on the water, and let it run, the water & coolant came out of the feed side discharging kinda slow, then it got fast. So it was a restricted/partially heater core !I droveit and raised it again, let itcool, topped off the radiator. Drove it again, the temp gauge right on the button @ 195* There must have been some crap that collected in there when I did the intake manifold, ect.. I found some pieces of rust/scale/crap in the driveway after I did this. Just hope that's it now !!!Thanks Peru At my wits END

 

Sure hope this resovles your problem. A lesson learned - don't neglect the coolant system.

 

I just bought the vehicle- No lesson learned- Just that Gm should had continued that class action against them for that crap- DEXCOOL, Never heard of gaskets getting eaten away by coolant and totally corroding these engines !!!!! Gm had a lesson LEARNED !!!! IT"S NO WONDER WHY GM IS GOINGUNDER !

http://www.consumeraffairs.com/news0...m_dexcool.html

 

Sorry, you're not selling the Dexcool issue to me. The problem was with the design and materials used in the intake gasket. Research will show that there are lots and lots of engines from GM that were initially filled with Dexcool that have not had these issues. GM should have used a different gasket design. The lesson I was referring to was for future maintenance, not past.

 

I could CARE less of YOUR or anyone else POINT ON THIS ISSUE- bottom line is, THEY WERE SUED, IS WAS PROVEN, AND THEY PAID, PERIOD . Ya think they wanted to pay out hundreds of thousands of dollars ! No need to argue about it, they got theirs, Maybe R & D shoulda done some more research on that crap !! Simple as that. Why don't you pour some Liquid Acid in there! Same result- Eating from the inside out, Ever do motor work on a old NEGLECTED car ? Ever see coolant do that, NO WAY PAL. I've ended my conversation with you on this! Just think about it !

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